HATTIESBURG, Miss. — Just more than halfway into his 12-minute stump speech, former Rep. Gene Taylor answered the question hanging over his primary challenge to the Republican that defeated him in 2010.

After representing the area for 21 years as a Democrat, why switch parties?

“I’ll make it very simple,” Taylor told a friendly crowd of a couple dozen after conducting a live interview with the local NBC affiliate. “When I first went to Congress, almost all of the southern Democrats were pro-life, almost all of them were for Second Amendment rights, almost all of them believed in a strong national defense, and almost all of them believed in a balanced budget. Over the years that changed.”

In the wake of the 2010 GOP wave, it didn't look like either of the state's losing Democratic congressmen would be coming back any time soon. But with last-minute candidate filings three months ago, both Taylor, who is taking on GOP Rep. Steven M. Palazzo in the 4th District as a Republican, and Travis Childers, who represented the 1st District for three years and is now running for Senate, are giving it a shot.

On Tuesday, both could learn the fates of their unlikely bids, as Taylor battles in a Republican primary and Childers watches the consequential GOP Senate primary. In an interview earlier in the afternoon, about 90 minutes west at a Days Inn in McComb and just before he would address a couple dozen Democrats, Childers conceded his chances would likely be greater against state Sen. Chris McDaniel than six-term Sen. Thad Cochran.

“Potentially, this U.S. Senate seat is an open seat,” said Childers, 56, who still sports a thin mustache. “It very well may not be. But if it is, I think I would regret having missed that opportunity.”

Childers is interviewed by Roll Call. (Tom Williams/CQ Roll Call)

On yet another rainy day in May in south Mississippi, Childers said he’s avoiding the tumultuous storm that is the GOP nomination fight. As long of a shot as it is for a Democrat to win a Senate seat in Mississippi no matter the Republican opponent — it hasn’t happened since 1982 — Childers is laying the groundwork for a competitive race and pitching himself as the kind of moderate Democrat who could potentially appeal to voters statewide under the right circumstances.

“They can talk about each other all they want to, they can slander each other on TV ads,” Childers said. “I’m going to continue what I’m doing, driving around this state, continue to introduce myself to people who don’t know me, renew old acquaintances and friendships — that’s not going to change my direction.”

Until he opens his mouth, Taylor, 60, with bronze skin and blonde hair, could pass for a surfer from Southern California. But he’s a lifelong Gulf Coast resident and former Coast Guard reservist who is deeply concerned about the fate of the area's military installations, particularly Keesler Air Force Base, and the coast's ability to get future federal disaster aid — thanks to Palazzo's vote against it elsewhere.

That’s why he’s challenging the incumbent and running in the GOP primary after serving 10 and a half terms as a Democrat. Another convenient circumstance: President Barack Obama lost the 4th District twice with 31 percent.

As one drives down Hardy Street in Hattiesburg past Taylor’s regional campaign headquarters, it’s impossible to miss his digital billboards and yard signs, which — like his bumper stickers — feature the GOP’s elephant logo.

But Palazzo is working to remind voters of Taylor’s Democratic history. A Palazzo ad labels Taylor a “lifelong Democrat” and a narrator tells viewers the former congressman supported Rep. Nancy Pelosi, D-Calif., for speaker — the same line of attack he used in 2010. Taylor supporters say it was Palazzo’s best and only angle then, since Taylor actually boasts a conservative record.

Chris Perkins, a Republican who challenged Rep. Gerald E. Connolly, D-Va., in 2012, was on hand at the Taylor event for moral support. Joel Dunagin, a longtime friend of Taylor, introduced the former member to the crowd: “He’s a true conservative. Whatever party he chooses, he’s a conservative.” Later, in an interview, Dunagin said the Democratic Party left many conservatives in Mississippi, and Taylor is just the latest to make the switch.

While he's no longer a Democrat, there is speculation Taylor could receive a boost in the open primary from Democrats participating in the GOP election to vote for him over the incumbent. If no one in the five-candidate field takes more than 50 percent, the race could extend another three weeks until a June 24 one-on-one runoff.

Childers delivered his speech to a racially diverse but mostly older crowd. He is friendly and engaging as a retail politician, and used terms like "kinfolk" and "babychild." He hails from up north in Prentiss County, just north of Tupelo, and asked the McComb Democrats at different points if they used those terms down south, too. They do.

He was less confident of victory than Taylor, but asked for a commitment from the supporters on hand to help in his efforts — and confirmed he is all in no matter the outcome on Tuesday.

“I don’t know that I can [win],” Childers said, “but to my fellow Democrats in this room, we won’t know if we don’t try.”